Ore-concentrator.



N0.847,286. v PATENTED MAR.12,190-7. A. 0. CAMPBELL.

ORE OONGENTRATOK urmomzon FILED 133.17, 1904. RENEWED SEPT. 14. 1906.

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WITNESSES: INVENTOR Arm/2N5 H len/20656327915193 V UNITED STATES PATET orrron.

" ORE-CONCENTRATOR.

Specification of Letters Patent.

Patented March 12, 1907.

Application filed February 17, 1904. Renewed September 14, 1906. Serial No. 834,599.

To aIZZ whom it may concern.-

Be it known that I, ALoNzo CLARENCE CAMPBELL, a citizen of the United States, and a resident of Asheville, in the county of Buncombe and State of North Carolina, have invented a new and Improved Cre- Concentrator, of which the following is a full, clear, and exact description.

This invention relates particularly to pneumatic ore-concentrators, an object be ing to provide a concentrator of simple c011- struction and by means of which the work may be-rapidly carried on and a thorough separation secured.

I will describe an ore-concentrator embodying my invention and then point out the novel features in the appended claims.

Reference is to be had to the accompanying drawings, forming a part of this specification, in which similar characters of reference indicate corresponding parts in all the figures.

Figure 1 is a sectional elevation of an orcconcentrator embodying my invention. Fig. 2 is a front elevation with the casing-top removed and a portion of the end wall broken away. Fig. 3 is a sectional detail showing the riffle arrangement. Fig. 4 is a section on the line 4 4 of Fig. 3. Fig. 5 is a sectional View of an actuating-wheel employed. Fig. 6 is a plan view illustrating a portion of a riflie, and Figs. 7, 8, and 9 show the actuating-wheel in different positions. I

The machine comprises a box or casing 1., mounted on suitable legs 2, and arranged at a downward angle toward the outlet end. Also arranged in the casing is a series of riffles 3, which practically formthe top wall of a lower chamber 4 and the bottom wall of an upper chamber 5, the top wall of said upper chamber being formed by a rigid cover 6. It will be noted that the riffles are inclined downward toward the outlet end of the machine and also inclined with relation to the top and bottom walls of the casing, thus forming what I term the converging chamber 4, the object of which will hereinafter be described. The chamber 5 communicates with a receivingcasing 7, and through the top wall of this receiving-chamber a feed-pipe 8 extends, the said feed-pipe terminating slightly above the riflies, as

clearly indicated in Fig. 1. The casing communicates with a compressor 9 through a flexible or pliable pipe 10, and at the inner end the communication is controlled by a compound flap-valve 11. This valve will be closed and opened by air-pressure, as will be hereinafter described. The compressor also communicates with the chamber 4 through a flexible or pliable pipe 1.2, at the end of which, within the chamber, is a compound flap-valve 13. The compressor is shown in the form of a bellows fixed to uprights 14, and within the bellows is an expanding spring 1.5 for moving the swinging part of the bellows in one direction. The object of the flexible or pliable pipes 1.0 12 is to avoid any jarring or agitation being communicated to the jig-box by the action of the mechanism or bellows, as will appear.

The compressor is actuated at rapid intervals by means of a connecting-rod 16, attached at its outer end to the swinging part ofthe bellows by means of a metal strap 17, provided with a suitable opening through which the rod passes. Nuts engage with the rod at opposite sides of the strap 17, and between the nuts and the strap are yielding washers 18, consisting, preferably, of rubber. This joint or connection is designed to permit of a slight up-and-down movement by the yielding of the washers.

The inner end of the rod 16 has a downwardly-extended hook portion 19, which passes into an annular channel 20 in an actuating-wheel 21, mounted on the shaft 22, having fast and loose pulleys 23 24 on its outer end. Each revolution of the wheel 21 is designed to actuate the compressor. Arranged at one point within the channel 20 is an abutment for engaging the hook 19. This abutment, as here shown, consists of a bolt 25, seated below the main portion of the base of the channel 20; but at the engaging side of said abutment the channel is deepened, as clearly indicated in Fig. 1. The hook will retain engagement with the pin until it is disengaged by the curvature of the wheel crowding against the shank of the hook, as indicated in Fig. 8, and during the remainder of the rotation of the wheel the hook end of the rod. will ride upon the base-surface of the channel, as indicated in Fig. 9. r The object of this construction is to give a short instantaneous impulse to the compressor.

The actuating-wheel 21 also serves as a flywheel, and arranged at intervals around the periphery of the wheel are tappet-blocks26, preferably made of Babbitt metal. These tappet-blocks are designed to engage successively with a spring-plate 27, attached to the under side of the box or casing. Each tappet strikes the spring at every revolution of the wheel, communicating an acoustic vibration to the bottom of the box and to the entire structure of the machine, the object of which will appear.

The riffies 8 are of metal, provided with perforations 28, and at the outlet edge of each riffle there is an upward extension 29, which is also perforated. The body portions of the riffles are overlapped, as clearly shown in the drawings, and adjacent rifljles are spaced apart by saw-cuts of suitable angle formed in side pieces 30, secured to the sides of the box or casing. Above these strips are strips 31, while below the strips 30 are strips 32. The spacings between riflies should be a degree larger than the size of the stuff under treatment, and the body portions of the riflies are slightly inclined upward toward the outlet. loaded, the material will flow into the spacings and form a natural angle of slope of about forty-five degrees. The material should not flow through by force of gravity or impact of air alone, but may be induced to do so by additional force or action, as will hereinafter appear. 1

The object of the converging space that is within the chamber 4 is to afford an equal flow of air at all points within the jig-surface. The passages between the riflies serve a double purpose-namely, for the flow of the concentrates downward on the lower surfaces of the riffles, also for the flow of the air upward and toward the outlet end of the machine.

Arranged in the upper chamber 5 is an endless retarding-conveyer, here shown as comprising chains 33, to which blades 34 are at tached, which are designed to go through to the bottom of the bed of material and to contact with the riffles. The chains of the conveyer extend around sprockets 35, arranged at the upper end of the chamber, and around sprockets 36 mounted on a shaft 37 at the lower end of the conveyer, and to im part a slow motion to the conveyer I employ aworm-gearing. As here shown, a wormwheel 38 is engaged by a worm 39,0n the outer end of the shaft of which is a band wheel 40.

The inclined bottom of the box or casing is 'provided at intervals with discharge-tubes '41, and extended across the bottom 1 of the casing at the lower side of the pipe-inlets are dam-strips 42. At the lower portion of the casing a discharge-pipe 43 leads to the bot tom of the casing, and below the inlet to said pipe a dam is formed by a cross-plate 44. Between the end wall of the casing and the cross-plate 44 a pocket 45 is formed for receiving tailings, which are carried off through the pipe 46.

Having described the different parts of the When the riffle-surface is 7 mechanism, 1 will now describe the process of operation. Supposing that the machine be applied as an a1r-jig for concentrating finelydivided ore, since the provisions of the in vention are for treatment of the fine stuff that has not been sized, the storage-bin above supplies the material through the feedpipe 8 and enters the jig above the riflles and A at the upper end forms into piles on the head riffles. This accumulation will stop the flow of stuff until it is removed by the conveyerblades as the stuff passes underneath the feed-gate 47. The wheel 21 actuates the bel lows at each rotation, as heretofore stated, and the tappets 26 put into violent vibration the spring 27. The impulses of air sent are into the spaces under the riflies with great rapidity and intensity. The lower valve 13 opens the upper valve 11, closing at the instant of impulse, and the air passes through the spacings and perforations of the riffies and permeates the bed of the material until the air in the upper chamber is of the same pressure as the air in the lower chamberthat is, when there is an equilibrium of pressure the air will be at a standstill. At the instant of reverse action of the bellows, caused by the spring 15, the upper valve opens and the lower valve closes, thus exhausting the air from the upper chamber, and in turn from the lower chamber through the bed of material until there is an equilibrium of pressures. It will be understood that both the to and fro actions of the bellows cause a flow of air through the spacings and perforations and through the'bed; but

this flow is cushioned, since each action is against increasing resistance in compressing and expanding thetwo volumes of air conlined above or below the riffles.

The stuff on the bed is classified in the usual way, the dense stuff settling on the riffles and in the spacings. The action of the spring 27 sets the rifiles into violent vibrations and causes the dense stuff to flow from the inside margins of the riflies into the concentrate-chamber under the riflies, while the less dense stuff is manipulated by the retarding-conveyer. The very slow speed ofthe conveyer retards the how of stuff, which otherwise would move at too rapid arate and would not afford sufficient time to insure satisfactory work. Since the stuff is not sized, there will be a portion that is exceedingly fine as compared to other portions. When all these variable grades of sizes and densities are left to the free action of the air aided by gravity without the retarding devices, the fine stuff will immediately flow away from the coarse stuff of the same density and there will be every rate of velocity of flow, the finest stuff at all times discharging most rapidly and each grade in order of size of grain.

The object of the conveyer is to insure that all the mixed grades and densities shall move at one fixed and invariable-rate except that portion of the concentrates destined to go through the spacings and perforations and fall into the concentrate-chamber, as already explained.

It will be understood that the blades 34 are so excessively deep that the stuff cannot overflow or underflow, but must remain securely pocketed, traveling from top to bottom of the incline. In this well-regulated transit the fine stuff has the same kind of treatment as the coarse stuff, which does not require so much time, but for the action of the blades, which serve as governors, the coarse stufi' being much more easily and quickly concentrated.

The tailings are discharged automatically at the lower end just as the stuff is fed automatically at the upper end. The discharge above the first dam 42 in the concentratesbox catches most of the dense stuff. The second dam holds and discharges the secondgrade stuff, and the intense vibration imparted by the spring 27 serves to prevent any accumulation of concentrates in the box, since it flows out through the passages as fast as it falls from the riflies.

Having thus described my invention, I claim as new and desire to secure by Letters Patent- 1. An ore-concentrator comprising a casing, a series of riffies arranged at a downward incline in said casing, a compressor at one end of the casing having communication with the casing above and below the riflies, and oppositely-opening valves for controlling said communications.

2. An ore-concentrator comprising an airtight casing, a series of overlapping riifies having a downward incline in said casing, a compressor at one end of the casing communicating with said casing, above and below the rifiles, a retarding-conveyer operating in the chamber above the riffles and a worm gearing for operating the conveyer.

3. An ore-concentrator comprising an airtight casing, a series of overlapping riffles having a downward incline in said casing, a compressor at one end of the casing communicating with said casing above and below the rifiles, and a retarding-conveyer operating in the chamber above the riffles with a slow motion.

4. A jig or concentrator having superimposed overlapping spaced perforated riflles.

5. A jig or concentrator having overlap ping perforated rifiies spaced one above another and having upturned portions at the outlet ends.

6. In a jig or concentrator, a series of I riflies consisting of overlapping plates, the series being arranged at a downward angle toward the outlet end, and each riffle being inclined slightly upward toward its outlet end.

7; I11 a concentrator, a casing, a' series of riflles in the casing, an air-compressor having communication with the casing above and below the riffies, an actuating-wheel having a peripheral channel, an abutment arranged in said channel, the channel being deepened at the engaging side of the abutment, and a compressor-actuating rod operated by engaging with the said abutment.

8. A concentrator comprising a casing, riflies in the casing, an air-compressor having communication with the casing, an actuating-wheel having a peripheral channel, a bolt extended across said channel and forming an abutment, a rod having a hook end for engaging with said abutment, a connection between the other end of said rod and the compressor, and means carried by said actuating-wheel for imparting vibratory motion to the concentrator.

9. A concentrator comprising a casing, a series of riffies in the casing dividingit into upper and lower chambers, an air-compressor, a pliable pipe providing communication between} the compressor and the lower chamber, multiple valves at the end of said pipe within the chamber, a pliable pipe providing communication between the compressor and the upper chamber, and valves at the end of said pipe within the compressor.

10. A concentrator comprising a casing, a series of riffles arranged therein, an air-compressor having communication with the casing above and below the riflies, the said compressor consisting of a bellows, a rod extended from the movable part. of said bellows and having a hook end, an actuating-wheel having a peripheral channel for receiving said hook end, an abutment in the channel for engaging with the hook end, tappet-blocks arranged at intervals on the periphery of the wheel, and a spring-plate secured to the bot tom of the casing for engagement with said tappet-blocks.

In testimony whereof I have signed my name to this specification in the presence of two subscribing witnesses.

- ALONZO CLARENCE CAMPBELL.

Witnesses:

A. B. MOORE, KATE B. HACKNEY. 

